Newton, Adam, and the Apple

When Newton saw an apple fall, he found In that slight startle from his contemplation— 'Tis said (for I'll not answer above ground For any sage's creed or calculation)— A mode of proving that the earth turn'd round In a most natural whirl, called 'gravitation'; And this is the sole mortal who could grapple, Since Adam, with a fall, or with an apple.